Which brand of slip meters do you suggest?

Hello everyone! I work in the maintenance department at a retail shopping center and have been asked to purchase a slip meter to test the traction on all of our flooring. I’ve looked around on Google a little bit but would like to get some opinions from people on here. Is one brand better than another and about how much should I be expecting to spend?

My husband is a contractor and he says that he suggest checking with a company called Johnny Grip. You can purchase them directly online from multiple places but just tell your supervisor to be expecting to shell out around $800. But hey, at least YOU don't have to pay for the bill! :D